I loved Asphalt3D's Ringosaurus model, but was not properly balanced (would fall on its face) and the pocket was not deep enough to hold anything.
Since Asphalt3D published only the STL, I decided to rebuild it from scratch in xShape. Many thanks to @GC for recording amazing tutorials and for helping me to start the model.
Now not only the head can hold rings, but also the tail.
I attached the 3DXML in case you want to further modify it. You can download the print profile from here:
https://makerworld.com/en/models/57828#profileId-59525
xshape